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Improved Channel Reciprocity for Secure Communication in Next Generation Wireless Systems

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Computers, Materials & Continua 2021年第5期67卷 2619-2630页

作者： Imtisal Qadeer muhammad Khurram ehsan Faculty of Engineering Bahria UniversityLahore CampusLahorePakistan

To secure the wireless connection between devices with low computational power has been a challenging problem due to heterogeneity in operating devices,device to device communication in Internet of Things(IoTs)and 5G wireless *** layer key generation(PLKG)tackles this secrecy problem by introducing private keys among two connecting devices through wireless *** this paper,relative calibration is used as a method to enhance channel reciprocity which in turn increases the performance of the key generation *** reciprocity based key generation is emerged as better PLKG methodology to obtain secure wireless connection in IoTs and 5G *** deconvolution is proposed as a promising technique for relative calibration to ensure channel reciprocity in comparison to existing techniques Total Least Square(TLS)and Structured Total Least Square(STLS).The proposed deconvolution technique replicates the performance of the STLS by exploiting the possibility of higher information reuse and its lesser computational complexity leads to less processing time in comparison to the *** presented idea is validated by observing the relation between signalto-noise ratio(SNR)and the correlation coefficient of the corresponding channel measurements between communicating parties.

关键词： Channel measurements physical layer key generation channel reciprocity Internet of things deconvolution

Statistical Inference of User Experience of Multichannel Audio on Mobile Phones

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Computers, Materials & Continua 2020年第11期65卷 1253-1270页

作者： Fesal Toosy muhammad Sarwar ehsan University of Central Punjab Lahore54700Pakistan

Mobile phones and other handheld electronic devices are now ubiquitous and play an important role in our everyday *** the last decade,we have seen a sharp rise in the sophistication of both hardware and software for these devices,thus significantly increasing their utility and *** devices are now commonly used for the streaming of audio and video and for the regular playback of *** audio has now become a popular format and with recent updates in software,the latest audio codecs that support this format can effectively be played back on most electronic *** a result,more audio content that is now compatible with these devices is being *** is important to perform subjective quality tests for multichannel audio verses traditional stereo and mono on devices like mobile phones while using *** paper presents the results and analysis of such listening tests that evaluate basic audio quality and quality of *** results show that while multichannel audio scores higher than stereo and mono for both of these attributes,the difference in score was less for the ratings of quality of *** results were processed using an Analysis of Variance(ANOVA)to show the statistical *** of the effect size showed that the audio content had little bearing on the results.

关键词： Subjective assessment multichannel audio MUSHRA listening test

Quantization and Event-Triggered Policy Design for Encrypted Networked Control

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 946-955页

作者： Yongxia Shi ehsan Nekouei the Department of Electrical Engineering City University of Hong KongHong KongChina

This paper proposes a novel event-driven encrypted control framework for linear networked control systems(NCSs),which relies on two modified uniform quantization policies,the Paillier cryptosystem,and an event-triggered *** to the fact that only integers can work in the Pailler cryptosystem,both the real-valued control gain and system state need to be first quantized before *** is dramatically different from the existing quantized control methods,where only the quantization of a single value,e.g.,the control input or the system state,is *** handle this issue,static and dynamic quantization policies are presented,which achieve the desired integer conversions and guarantee asymptotic convergence of the quantized system state to the ***,the quantized system state is encrypted and sent to the controller when the triggering condition,specified by a state-based event-triggered strategy,is *** doing so,not only the security and confidentiality of data transmitted over the communication network are protected,but also the ciphertext expansion phenomenon can be ***,by tactfully designing the quantization sensitivities and triggering error,the proposed event-driven encrypted control framework ensures the asymptotic stability of the overall closedloop ***,a simulation example of the secure motion control for an inverted pendulum cart system is presented to evaluate the effectiveness of the theoretical results.

关键词： Cyber-security encrypted control event-triggered control(ETC) networked control systems(NCSs) semi-homomorphic encryption

Visible-Light Photocatalytic Conversion of Carbon Dioxide into Methane Using Cu_(2)O/TiO_(2) Hollow Nanospheres

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中国化学:英文版 2015年第1期33卷 112-118页

作者： Feng Bi muhammad Fahad ehsan Wei Liu Tao He School of Chemistry and Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China National Center for Nanoscience and Technology Beijing 100190China

In the past few decades there has been a remarkable rise in the study of visible-light photocatalytic reduction of carbon dioxide (CO_(2)) into value-added chemicals such as methane (CH4) with water as reducing agent in order to prevent global warming and energy crisis. However, so far the conversion efficiency leaves much to be enhanced under sunlight irradiation. In this work, Cu_(2)O hollow nanospheres were synthesized via soft-template method and were combined with TiO_(2) through in-situ hydrolysis of Ti(OBu)4 under sonication. The obtained photocatalysts of Cu_(2)O and Cu_(2)O/TiO_(2) composite were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, UV-visible diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. Compared to Cu_(2)O hollow nanospheres, the Cu_(2)O/TiO_(2) composite exhibited higher efficiency in photocatalytic reduction of CO_(2) into CH4 under visible-light irradiation (λ≥420 nm). This is because of the formation of a p-n heterojunction in the composites, resulting in efficient suppression of recombina- tion of the photogenerated electrons and holes as well as an improved stability of the catalyst and, thereby, the im- proved visible-light photocatalytic activity.

关键词： photoreduction carbon dioxide methane hollow nanosphere cuprous oxide titanium dioxide

基于GEO数据库和生物信息学分析的甲状腺肿瘤关键基因筛选

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基于GEO数据库和生物信息学分析的甲状腺肿瘤关键基因筛选

作者： muhammad Hasnain ehsan Ullah 中南大学

学位级别：硕士

背景:甲状腺位于甲状软骨下方和两侧并构成内分泌系统的一部分参与体内激素水平的调节。当正常甲状腺组织生长脱离既定的成熟轨迹,肿瘤也因此而生。甲状腺肿瘤作为起源于甲状腺组织的内分泌肿瘤近年来在全球发生率增长迅速,已逐渐成为... 详细信息

背景:甲状腺位于甲状软骨下方和两侧并构成内分泌系统的一部分参与体内激素水平的调节。当正常甲状腺组织生长脱离既定的成熟轨迹,肿瘤也因此而生。甲状腺肿瘤作为起源于甲状腺组织的内分泌肿瘤近年来在全球发生率增长迅速,已逐渐成为最常见的肿瘤之一。从具有高度侵袭性的未分化甲状腺癌到相对呈现惰性的分化型甲状腺肿瘤,甲状腺肿瘤的类型和预后均展现出多样的类型。大多数甲状腺癌起源于滤泡上皮细胞,并分化成为存在恶性程度差异的各类甲状腺肿瘤。未分化甲状腺癌虽然稀少,但却因侵袭性强而引起患病人群生存率水平较低;而甲状腺乳头状癌作为甲状腺最常见的类型,几乎占所有甲状腺恶性肿瘤的85%,患病人群的预后却相较而言远胜于其他类型肿瘤的预后。因此,在甲状腺肿瘤诊断与治疗过程中,分化型甲状腺肿瘤相对较好的预后与目前积极的治疗决策存在一定的矛盾,早期区别预后差异的甲状腺肿瘤并为进一步治疗提供更加精准的指导方案仍然是悬而未决的问题,而且甲状腺结节与肿瘤的鉴别也依然呈现出了进一步明确的需求和可能。鉴于甲状腺肿瘤的早期阶段没有典型症状,通过基因诊断及早发现甲状腺肿瘤尤其是侵袭性较高的甲状腺肿瘤,对于指导治疗和改善甲状腺肿瘤预后也显得至关重要。在这样的前提下,更加深入的了解甲状腺肿瘤形成的分子水平机制成为可能进一步解释甚至解决问题的方式,而近年来基因芯片和高通量测序等技术对比不同组织类型中基因的表达水平并获取组织差异数据等方法也发展迅速,这些技术和研究理论的发展与广泛应用极大程度的增进了对于基因表达等分子水平的了解,也同时拓展了认识甲状腺肿瘤的途径,进而提供了指导诊断和治疗实践的可能。在对分子水平的探索中,逐渐发现不同组织类型下潜藏着的是具备着一定特点的基因改变,例如BRAF、NRAS、HRAS和KRAS这样的基因向致癌方向发生突变就被发现存在于约75%的甲状腺乳头状癌,其中BRAF V600E几乎是最常见的类型。PI3K/AKT信号通路上的突变(如PIK3CA、PTEN和m TOR等)也常被发现于多种侵袭性较高的甲状腺肿瘤中。此外,RET、BRAF、NTRK、ALK和THADA等基因的融合也常见于部分甲状腺乳头状癌中而极少见于其他类型之中。此外,PAX8/PPAR基因的融合发生于甲状腺滤泡状细胞癌,TP53和TERT启动子在未分化甲状腺癌的变异也被广泛认知。在借助计算机科学与信息技术处理庞杂数据的优势,对繁多的基因数据进行处理并关联既往研究,萃取生命进展与疾病形成、发展的可能理论逐渐成为一种完善既往研究或指导进一步探索的方式,而比肿瘤组织与正常组织间差异实现对肿瘤发生发展的探索已成为较为常见的方法。综上,以生物信息学技术探索甲状腺肿瘤相关的基因靶点,进而尝试回答甲状腺肿瘤诊治过程中存在的矛盾与问题也成为可行方案。目的:本研究的目的在于使用多种生物信息学方法分析肿瘤分组和正常分组差异,尝试探索甲状腺肿瘤相关的基因靶点,进而协助发现有益于诊断和治疗的方案。方法:在本研究中,我们将借助生物信息学的技术分析甲状腺肿瘤组织与正常组织间差异。首先从基因表达综合数据库(GEO)中下载的三组数据,每组数据中都涵盖着多个甲状腺肿瘤和正常组织的不同样本。将三组数据中的肿瘤组织与正常组织的样本数据经过GEO2R分别进行差异分析的计算后,下载依据GEO2R分析完成同时所绘制的火山图实现可视化处理,再通过对差异分析后的数据结果设定p值(<0.05)和log FC值(绝对值大于1)筛选出三组数据中肿瘤组织与正常组织对比分析后存在着显著表达差异的基因数据。获取显著差异基因数据后,将三组数据中存在显著表达差异的基因分别上传至网页绘图工具以获取它们的交集并绘制对应的韦恩(Venn)图。三组数据筛选后的差异基因中同时存在的基因即韦恩(Venn)图的中心交集数据将作为代表整体甲状腺肿瘤组织与正常组织的差异基因,进而以DAVID网页工具对它们进行功能相关的富集分析,结合既往已证实的研究记录及结果进行基因本体(GO)和京都基因与基因组百科全书(KEGG)通路分析并获取结果,以此推测差异基因作为整体或聚类分组后影响的生物过程、所参与的细胞成分、分子相关功能与参与的信号通路,即预测可能参与了甲状腺肿瘤组织区别于正常组织形成与成长过程中的发生发展方式。与此同时,上传上述分析后差异基因的交集至STRING数据库并获取基因对应蛋白,再设定网络构建与筛选条件后构建蛋白质相互作用(PPI)网络。以基因所对应蛋白之间的互相作用关系进而间接地探索基因之间的互相作用与关联,并推测它们实现影响生物进程互相作用的方式。获取的蛋白质互相作用网络数据从数据库下载后导入Cytoscape中进行绘图及可视化处理,并基于敏感且特异的枢纽蛋白或基因常呈现处于中心位置调节并影响多个蛋白或基因的理论,以Cytoscape中的计算引擎插件Cytohubb

关键词：甲状腺肿瘤差异基因功能富集蛋白互作网络 ROC曲线预后

Improving the Surface Roughness of Dental Implant Fixture by Considering the Size,Angle and Spraying Pressure of Sandblast Particles

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Journal of Bionic Engineering 2024年第1期21卷 303-324页

作者： ehsan Anbarzadeh Bijan Mohammadi School of Mechanical Engineering Iran University of Science and TechnologyTehranIran

In this study,different conditions of sandblasting on dental implant fixtures were investigated to achieve the best sandblasting conditions.18 different sandblasting conditions(Using 152 implant fixture samples)were examined,including parameters such as particle size,particle blasting pressure,and particle blasting *** surface treatment of the samples was performed using the SLA+Anodizing *** testing was performed for each of the 18 different states,and the average surface roughness of each of these was compared with each ***,a bone layer was placed on the sample with the closest average surface roughness to the standard and the least amount of aluminum oxide on its surface among the 18 different states,to confirm the accuracy and quality of the desired surface roughness by examining the bone formation process and *** results showed that state No.4(sandblast particle size:75µm,spraying pressure of sandblast particles:4 bar,sandblast particle spraying angle:30 degrees),which was prepared using the SLA+Anodizing method and had a surface roughness of 1.989µm(The percentage of Al_(2)O_(3)on the surface=6%),had the best sandblasting conditions and showed 95%cell viability and accelerated the treatment and bone formation process for about a *** simulation results,using Abaqus software,indicated that the stress distribution on the surface of the implant fixture in contact with the bone surface has increased by approximately 4.3%for state *** will help prevent loosening of the dental implant fixture over time.

关键词： Dental implants Surface treatment Sandblast Surface roughness Osseointegration

Suicide bomb attack causing penetrating craniocerebral injury

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Chinese Journal of Traumatology 2013年第1期16卷 51-53页

作者： Manzar Hussain muhammad ehsan Bari Department of Neurosurgery Dow University of HealthSciences Karachi 75300 Pakistan

尽管由于象小团和钉子一样的多重外国身体在战争有强风或射击损害的各种各样的报告，外国身体引起的渗透的服的损害在平民的 neurosurgical 损伤是稀罕的。在我们的情况中，一个 30 岁的人在自杀炸弹攻击以后与右边的软弱的症状介绍了... 详细信息

尽管由于象小团和钉子一样的多重外国身体在战争有强风或射击损害的各种各样的报告，外国身体引起的渗透的服的损害在平民的 neurosurgical 损伤是稀罕的。在我们的情况中，一个 30 岁的人在自杀炸弹攻击以后与右边的软弱的症状介绍了诊所给神经外科。颅骨 X 光检查显示出一根单个 intracranial 钉子。小颅骨切开术被做，钉子小心地被移开避免损害到包围正常大脑织物。在 6 ； months’他的 rightsided

关键词：炸弹攻击颅脑损伤穿透性神经外科地心引力指甲 X线片脑组织

Craniocerebral injuries in war against terrorism-a contemporary series from Pakistan

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Chinese Journal of Traumatology 2013年第3期16卷 149-157页

作者： muhammad Umair Bashir muhammad Zubair Tahir ehsan Bari Sehreen Mumtaz Department of Neurosurgery Aga Khan UniversityHospital Karachi Pakistan

Abstract：Terrorism-related bomb attacks on civilian population have increased dramatically over the last *** injuries secondary to improvised explosive devices have not been widely reported in the context of unarmored *** series intends to report the spectrum of these injuries secondary to suicidal and implanted bombs as encountered at the Aga Khan University Hospital,Pakistan (AKUH).Further,a few pertinent management guidelines have also been ***:The hospital database and clinical coding during a 5-year period were examined for head injuries secondary to terrorism-associated *** addition to patient demographics,data analysis for our series included initial Glasgow Coma Scale,presenting neurological complaints,associated non-neurological injuries,management (conservative or operative) to associated complications,and discharge neurological ***:A total of 16 patients were included in this *** them 9 were victims of suicidal blasts while 7 were exposed to implanted *** patients presented with diverse patterns of injury secondary to a variety of shrapnel.A follow-up record was available for 12 of the 16 patients (mean follow-up:7.8 months),with most patients having no active ***:The results of this series show that civilian victims of suicidal and improvised bombings present with a wide range of neurological symptoms and injury patterns,which often differ from the neurological injuries incurred by military personnel in similar situations,and thereby often require individualized care。

关键词： Brain injuries Craniocerebral trauma Decompressive craniectomy

Bearing capacity of circular footings on multi-layered sand-waste tire shreds reinforced with geogrids

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1085-1094页

作者： Mahmoud Ghazavi ehsan Khosroshahi Faculty of Civil Engineering K.N.Toosi University of TechnologyTehranIran

The presence of waste tires poses an environmental challenge as they occupy a significant amount of land and are expensive to dispose in ***,reusing waste tires can address this issue when waste tires are used in geotechnical *** determine the viability of this approach,laboratoryscale tests were conducted to investigate load-bearing capacity of circular footings on sand-tire shred(STS)mixtures with shredded waste tire contents of 5%e15%by weight and three different widths of *** investigation focused on analyzing the thickness of layers composed of STS mixtures,the soil cap,and the impact of geogrids on bearing *** results indicate that a specific mixture of sand and tire shreds provides the highest footing-bearing *** addition,the optimal shred content and size were found to be 10%by weight and 2 cm×10 cm,***,for a given tire shred width,a particular length provides the largest bearing *** results agree well with that of previous research conducted by the first author and his colleagues in direct shear and California bearing ratio(CBR)*** primary finding of this research is that the use of two-layered STS mixtures reinforced by geogrids significantly enhances the bearing capacity.

关键词： Geogrid Sand Waste tire shred Bearing capacity Waste tire shred optimization Tire shred aspect ratio